Granite outcrops are unique ecosystems in Georgia. They're basically exposed granitic rock formations in the Piedmont and Appalachian areas and for the most part, are nearly level. About 90% of the 12,000 acres of outcrops on montane areas of the South are in Georgia.
The Piedmont covers about one third of the state of Georgia (18,100 square miles) and is typically associated with rough hilly terrain in the north and gentle rolling hills further south. The Piedmont extends south from the mountains of north Georgia to the fall line and ranges from 500-1,500 feet in elevation. The fall line marks the boundary between the crystalline rocks of the northern part of the state and the mostly unconsolidated sediments of the coastal plain. It is thought to be the furthest inland extent of the prehistoric coastline. The fall line is often associated with waterfalls and rapids formed as rivers tumble from the Piedmont to the coastal plain.
Georgia boasts a large number of rock outcrops including the largest in the world, Stone Mountain. Rock outcrops can be either Manadnocks, which rise above the surrounding piedmont, or they can be simple flat-rock or pavement rock outcrops Most outcrops are composed of granite, an igneous rock that crystallized from slow cooling magma underground (intrusive igneous rock). The molten domes of magma that cooled to form our outcrops were generated from the heat and friction at the edges to colliding continental plates about 500 million years ago. The softer rock surrounding these granite domes gradually eroded away, leaving the granite exposed at ground level. In some cases, the granite was changed into gneiss (a metamorphic rock) due to high heat and pressure long before the surrounding rock eroded and exposed it.
Geologists estimate that most of the granitic rocks that outcrop in the Piedmont of the southeastern United States are approximately 300-350 million years old. These outcrops were formed by the intrusion of molten granite into preexisting country rock at a depth of about ten miles below the surface. Over millions of years, erosion removed thousands of feet of overlying rock, exposing the more resistant bodies of granite.
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1) What is the color that stands out as different on the rock in front of the one you are standing on ?
2) What interesting feature is behind you at the posted coordinates?
3) What do you notice about the shape of the rocks?
4) What angle would you say the angle of the rocks are the water is passing over?